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    <title>Document</title>
    <script>
        //更新变量
        var myname = '刘德华';
        console.log(myname);
        myname = '景甜';
        console.log(myname);
        //声明多个变量
        var age = 18,
            address = '红隐藏',
            gz = 2000;
        var sex;
        console.log(sex);
    </script>
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